ABSTRACT The reduction of risky college student drinking remains a national public health priority. Recent estimates suggest 2 in 5 college students frequently binge drink. Reports also indicate risky student drinking results in approximately 600,000 unintentional injuries, 700,000 physical assaults, and 97,000 sexual assaults annually. As alarming as these statistics may seem, they pale by comparison to mortality figures showing that every week another 50 families suffer the loss of a loved one due to student alcohol poisonings and accidents. Numerous studies have revealed protective behavioral strategies (PBS) show promise in helping reduce high- risk drinking and consequences in college students. Despite the benefits, there remains a sizeable gap in the literature detailing how consistently and how well drinkers use specific PBS. The proposed research will aid in the development of efforts to reduce risky drinking and consequences by employing a combination of qualitative and quantitative methods to systematically examine the effects of PBS consistency and quality. The research will be conducted in two phases. In phase I, the research will collect qualitative data on 60-80 students (18-23) via 6-8 focus groups to assist in the development of a theoretical model and a quantitative measure of consistency and quality of PBS implementation. This phase will also conduct psychometric testing for the quantitative measure of PBS implementation (n=100) (Aim 1). In phase II, the research will collect daily diary data on 216 students and an additional subsample of 100 non-college-attending adults (same ages as Phase I) across six weekends to examine between- and within-person differences in the consistency and quality of PBS implementation (Aim 2) and sex and college/non-college status as moderators of the relationship between PBS implementation (i.e., consistency, quality) and consequences (Aim 3). The research will: (1) add to the understanding of the dimensions of quality and consistency with which PBS are utilized, (2) provide more precise information about their efficacy in reducing consequences, (3) provide insights about areas where students are at an increased risk of experiencing harm, and (4) increase the public health impact of using PBS.